This mirrors the src/vctools/crt/github changes from Andrew Dean's …

…internal MSVC-PR-425243. (microsoft#3133)

Note that that PR must target `prod/be`, so this will result in temporary divergence between microsoft/STL's GitHub repo and the internal `prod/fe` branch (which we usually keep binary-identical at all times). I believe that this is tolerable because the `stl/msbuild` files change so rarely, and even if we do need to make changes (e.g. adding a new source file), there should be no major conflicts.

CMakeLists.txt

@@ -85,7 +85,7 @@ set(STL_LIBRARY_OUTPUT_DIRECTORY "${PROJECT_BINARY_DIR}/out/lib/${VCLIBS_I386_OR
 set(STL_RUNTIME_OUTPUT_DIRECTORY "${PROJECT_BINARY_DIR}/out/bin/${VCLIBS_I386_OR_AMD64}")
 add_compile_definitions(
     _ALLOW_ITERATOR_DEBUG_LEVEL_MISMATCH WIN32_LEAN_AND_MEAN STRICT _CRT_STDIO_ARBITRARY_WIDE_SPECIFIERS
-    _CRT_DECLARE_NONSTDC_NAMES=1 _WIN32_WINNT=0x0A00 NTDDI_VERSION=NTDDI_WIN10_CO)
+    _WIN32_WINNT=0x0A00 NTDDI_VERSION=NTDDI_WIN10_CO)
 
 if(STL_USE_ANALYZE)
     # TRANSITION OS-40109504: Windows SDK: incorrect SAL annotations on functions the STL uses